Vidkun Quisling | Biography, Nazi Collaborator, Cause of Death . . . Vidkun Quisling (born July 18, 1887, Fyresdal, Norway—died October 24, 1945, Akershus Fortress, Oslo) was a Norwegian army officer whose collaboration with Nazi Germany in their occupation of Norway during World War II established his name as a synonym for “traitor ” He was executed for treason and other crimes Quisling entered the Norwegian army in 1911 and served as military attaché